Arch.



D. B. LUTEN.

ARCH.

APPLIOATIOX FILED JULY e, 1911.

@@FQQ Patente May 64913 DANIEL B. LUTEN, OF INDIANAPOLS, ENDIABLL.

ARCH.

renonce.

Original application lecl April 24, 1505, Serial No. 257,165.

Specification of Letters Patent.

vindianapolis. iu the county of Marion and i State ot indiana. haveinvented a new and useful Improvement in Arches, of which the vfollowing is a specification.

illy invention relates to improvements iu arches and has for its purposeto provide an arch structure with its upper and lower surfaces curved inthe usual way transvers gitudinally ol the and concave outwardlyj andthe resulting structure "reinforced to produce `Qjreat strength withminiuuun materials and labor.

The present application constitutes a division ot' an application tiledby me April 2l, i905, Serial fio. 257,165.

The invention is illustrated in the accompanyimoT drawings in which thesaine reference characters designate like parts throughout the severalviews.

Figure l is a longitudinal section of an arch, Fig. is a transversesection at the crown. Figisa transverse section through the abutment,Fig; `rl; is a perspective view of a halt arch embodying' myimprovement, and Fig. 5 is a plan view of such an arch.

Theupper and lower surfaces of the arch are of the form of a warpedsurface somewhat similar to a shoe-horn, as shown in Fig. Ll. A surfacethat can be rolled out on a plane, as a cylinder or cone, or any otherdevelopable surface, which is 'necessarily generated by the motion ot ayright line in parallel or intersecting positions will crack easily alongone o the lines of generation when distorted; buty a warped or doublecurved surface of the form shown cannot cruel; or breal; along astraight line but must separate on a curved line. It is for this reasonthat the shoe-horn is so 'much stiffer and resists distortion so muchmore etliciently than would the same piece of metal it merely of theusual 'form of' arch without curvature longitudinal ot the arch axis. Itnew the :form of arch proposed be made ot concrete with steel embeddedacross the probable line of fracture this form of arch will require muchgreater stretch of the em- ;Patentc May 6., il.

Divided and this application :tiled July 8,

Serial No. 637,454.

bedded steel than the type of arch curved in one direction only. Andconsequently its strength would be greatly increased or the samestrength secured with decreased material.

Longitudinal tension rods are passed lon- 1 lefitudinally through thearch and at the h aunches are closely grouped near the tension edgeswhich are the upper outside edges or the arch near its ends. At thecrown ot' the arch they are more closely lo the axis of the arch. butalso curved longrouped near the center and preferably pass diagonallyacross the roadway. Thus as is shown in detail in Fig. lthe rods passnear the edges 4l at the haunches and near the center il2 at the crown.and while the rods 35 will be atl 4l on one side of the roadwayv forthat end of the arch these same rods will cross diagonally across theroadway through the crown ot' the arch to the corresponding edge on theother side of the roadway at the opposite end of the arch. The regionsof trreaest tension in such an arch will be when loaded with aconcentrated load at the crown, at the center at the crown and at thesides over the haunches. Hence such an arrangement of diagonal membersfor reinforcement eitectually reinforces the structure at its greatesttension regions. nd by this means the regions of greatest tension wheregreatest separation of the material would resultin case of fracture, arereinforced with rods or other members concentrated at those regions andwith the reinforcing`v members running in substantially straight linesthrough these tension regions.

, l claim l. A reinforced concrete arch comprising a concrete bodyhaving a cross-section of an inverted arch shape, and reinforcing medi-vbers embedded in the .arch and crossingA each other diagonally.

i2. A reinforced concrete arch having a cross-section of inverted archform, and with embedded reinforcing members concentrated near the middleat the crownand near the sides over the abntments.

3. concrete arch having;I a cross-section or inverted arch form, andreinforoingmembers embedded in the arch and substantially m :eeeeeeestraight through the tension regimi@ et my hand and see et indianapolis,'limiiarrm9 crown and heunehes. this 6th dej' of Jul A, D, wie thousande. A reinforced concrete arch having a nine hundred and e even..cross-section of inverted meh form, and 'DANXEL B. LUTEFILJ.4 [Leij 5with embedded reinforcing members e011- Witne'sses: Y

vceaeti'ated neer the middle et the crown. B. H. Meme,

f n Witness whereof, L'heve hereunto set PAUL KLINGENSMHH.

